Should we consider sarcopenia in pediatric patients with chronic kidney disease? A preliminary cross-sectional analysis.

BACKGROUND: Pediatric patients with chronic kidney disease (CKD) frequently present an inadequate nutritional profile and musculoskeletal impairments. We investigated sarcopenia and its related traits in children and adolescents with CKD. METHODS: A cross-sectional study that enrolled pediatric patients with CKD (≥ 4 and < 18 years old). Physical function was assessed by handgrip strength and the 60-s sit-to-stand (STS-60) tests. Body composition measurement was performed by bioelectrical impedance analysis and anthropometry through mid-upper arm circumference (MUAC). Normative reference values from healthy pediatrics were used for identifying poor physical function and low MUAC. Probable sarcopenia was considered as low handgrip strength, whereas sarcopenia was defined by adding low MUAC. RESULTS: Twenty-two pediatric patients with CKD (11 ± 4 years and 59% boys) were evaluated; eight on peritoneal dialysis (36%), six on hemodialysis (27%), and eight non-dialysis (36%). Regarding sarcopenia traits, we observed low physical function by handgrip strength and STS-60 in 59% and 100% of the patients, respectively, while low MUAC in 77%. Probable sarcopenia was found in 9% and sarcopenia in 50%, but prevalence did not differ among stages. Handgrip strength was strongly associated with MUAC (r = 0.90; p < 0.001); on the other hand, the STS-60 was not significantly associated with any of the body composition variables. CONCLUSION: Among pediatric patients with CKD, the prevalence of sarcopenia and its related traits was high. Nephrology professionals should consider the assessment of sarcopenia in this population, while more evidence is needed to determine its prognostic value. A higher resolution version of the Graphical abstract is available as Supplementary information.

No NFATC2 fusion in simple bone cyst of the jaw.

AIMS: Simple Bone Cysts (SBCs) predominantly occur in long bones and 59% harbour NFATC2 rearrangements. Jaw SBC is rare and was previously referred to as traumatic bone cyst. It can rarely occur in association with cemento-osseous dysplasia (COD). To determine whether jaw SBCs represent the same entity as SBC of the long bones, or if they have a different molecular signature, we collected 48 jaw SBC cases of 47 patients to assess NFATC2 rearrangement. METHODS AND RESULTS: Out of the 48 cases, 36 could be used for fluorescence in-situ hybridization (FISH), of which nine (two of which associated with COD) were successful using an NFATC2 split probe. The remaining cases failed to show adequate FISH signals. All nine cases lacked NFATC2 rearrangement and five of these showed no detectable gene fusions using Archer FusionPlex. CONCLUSION: In our study, NFATC2 rearrangement is absent in solitary jaw SBC (n = 7) and COD-associated SBC (n = 2). Our findings suggest that SBC presenting in the jaw is molecularly different from SBC in long bones. Future molecular studies may confirm the absence of clonal molecular aberrations in SBC of the jaw which would support a non-neoplastic, reactive origin.

De novo TRPV4 Leu619Pro variant causes a new channelopathy characterised by giant cell lesions of the jaws and skull, skeletal abnormalities and polyneuropathy.

BACKGROUND: Pathogenic germline variants in Transient Receptor Potential Vanilloid 4 Cation Channel (TRPV4) lead to channelopathies, which are phenotypically diverse and heterogeneous disorders grossly divided in neuromuscular disorders and skeletal dysplasia. We recently reported in sporadic giant cell lesions of the jaws (GCLJs) novel, somatic, heterozygous, gain-of-function mutations in TRPV4, at Met713. METHODS: Here we report two unrelated women with a de novo germline p.Leu619Pro TRPV4 variant and an overlapping systemic disorder affecting all organs individually described in TRPV4 channelopathies. RESULTS: From an early age, both patients had several lesions of the nervous system including progressive polyneuropathy, and multiple aggressive giant cell-rich lesions of the jaws and craniofacial/skull bones, and other skeletal lesions. One patient had a relatively milder disease phenotype possibly due to postzygotic somatic mosaicism. Indeed, the TRPV4 p.Leu619Pro variant was present at a lower frequency (variant allele frequency (VAF)=21.6%) than expected for a heterozygous variant as seen in the other proband, and showed variable regional frequency in the GCLJ (VAF ranging from 42% to 10%). In silico structural analysis suggests that the gain-of-function p.Leu619Pro alters the ion channel activity leading to constitutive ion leakage. CONCLUSION: Our findings define a novel polysystemic syndrome due to germline TRPV4 p.Leu619Pro and further extend the spectrum of TRPV4 channelopathies. They further highlight the convergence of TRPV4 mutations on different organ systems leading to complex phenotypes which are further mitigated by possible post-zygotic mosaicism. Treatment of this disorder is challenging, and surgical intervention of the GCLJ worsens the lesions, suggesting the future use of MEK inhibitors and TRPV4 antagonists as therapeutic modalities for unmet clinical needs.

Making sense of giant cell lesions of the jaws (GCLJ): lessons learned from next-generation sequencing.

Next-generation sequencing has revealed mutations in several bone-related lesions and was recently used to uncover the genetic basis of giant cell lesions of the jaws (GCLJ). Consistent with their benign nature, GCLJ show a low tumor mutation burden. They also harbor somatic, heterozygous, mutually exclusive mutations in TRPV4, KRAS, or FGFR1. These signature mutations occur only in a subset of lesional cells, suggesting the existence of a 'landscaping effect', with mutant cells inducing abnormal accumulation of non-mutant cells that form the tumor mass. Osteoclast-rich lesions with histological similarities to GCLJ can occur in the jaws sporadically or in association with genetically inherited syndromes. Based on recent results, the pathogenesis of a subgroup of sporadic GCLJ seems closely related to non-ossifying fibroma of long bones, with both lesions sharing MAPK pathway-activating mutations. In this review, we extrapolate from these recent findings to contextualize GCLJ genetics and we highlight the therapeutic implications of this new information. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Patient-derived xenografts of a case of ameloblastic fibrodentinoma.

OBJECTIVES: The establishment of animal models of xenotransplantation can contribute to the elucidation of the molecular pathogenesis of ameloblastic fibrodentinomas (AFD) and it also provides an opportunity for drug tests. We aimed to evaluate the possibility of AFD tumour growth in a patient-derived xenograft (PDX) model. In addition, we characterized the human tumour and the PDXs. MATERIALS AND METHODS: A sample of a recurrent AFD was obtained and two fragments were contralaterally implanted subcutaneously in an 8-week old female NUDE mouse. After 250 days, the PDXs were removed and submitted to histopathological and molecular analysis. Immunohistochemical reactions for Ki67 and the phosphorylated form of ERK1/2 were carried out in both, PDXs and human tumour, and the presence of BRAFV600E was assessed. RESULTS: From day 135 onwards, the PDXs presented a growth peak and remained stable until day 250. Histopathologically, the PDXs presented the same features of the patient's tumour. Tumour cells exhibited Ki67 and pERK1/2 immunoexpression in the patient's tumour and PDX. The AFD was wild-type for BRAFV600E. CONCLUSION: The PDX model recapitulated well the human tumour after a long implantation time, representing a possible model to study the AFD and other odontogenic tumours pathobiology.

Peripheral giant cell granuloma associated with dental implants: a systematic review.

The purpose of the present review was to integrate the available published data on peripheral giant cell granuloma (PGCG) associated with dental implants into a comprehensive analysis of its clinical/radiologic features. An electronic search was undertaken in February/2018 in three databases, looking for publications reporting cases of PGCGs associated with dental implants. Nineteen publications were included, reporting 37 implant-associated PGCG. These lesions are more prevalent in women, in mandible, and in posterior regions of the jaws. Both 'excision alone' and 'excision + curettage' presented high recurrence rates (40% and 31.3%, respectively). The etiology of implant-associated PGCG has not yet been determined. Despite the small number of cases reported, implant-associated PGCG shows a high recurrence rate (1/3) for a benign non-neoplastic lesion and sometimes it requires the removal of the associated implant in order to prevent further recurrences. This recurrence rate is not affected by curettage after excision.

A potential new oral mapping (OM) method in the clinical evaluation and documentation of oral submucous fibrosis-A prospective clinical crossover study.

BACKGROUND: Despite much research, there is a lack of a definite protocol or method for documenting oral submucous fibrosis (OSMF) site presentation. In this study, we propose a new potential oral mapping (OM) method and evaluated its use in recording OSMF-affected mucosal sites. METHODS: Fifty OSMF patients were evaluated by 15 primary care dental practitioners using both, a conventional subjective recording method and a new OM method, to document the degree of involvement of affected oral mucosa with a crossover study design. Mann-Whitney test (non-parametric test) was used to make comparison between groups to determine any significant differences between the two identification methods. Wilcoxon tests were used to evaluate any significant differences in the difficulty in identification of two methods. RESULTS: There was a low agreement between the two methods used to detect OSMF in affected mucosal surfaces (P-value < 0.0001). More lesions were identified using the proposed OM method, and less discrepancy was found among dental practitioners. A difference in difficulty of OSMF documentation was found (Wilcoxon z = 3.615, P-value < 0.001), with the proposed OM method found to be easier. CONCLUSION: The proposed OM method appears to be useful for documentation, can easily be adapted in clinical practice, and effectively administered in clinical research. Additionally, it could be a useful tool to helping to maintain an OSMF database.

The relationship of "shisha" (water pipe) smoking to the risk of head and neck cancer.

INTRODUCTION: There has been a recent rise in popularity of waterpipe smoking (WPS) among younger people. While it is a tobacco-related product, research on the possible deleterious effects on health and its relationship with cancer is sparse. In this paper, we evaluated the existing literature and association of WPS with head and neck cancer. MATERIALS AND METHODS: PubMed, EMBASE, Scopus, Web of Science and grey literature from January 1990 up to and including March 2017 were searched. Two independent reviewers performed the study selection according to eligibility criteria. RESULTS: A total of seven studies that met the eligibility criteria were included. In four studies that evaluated the associated risk of oesophageal cancer, the odds ratio (OR) ranged from 1.69 (95% CI = 0.76-3.77) to 21.4 (95% CI = 11.6-39.5). The OR for the association of WPS with nasopharyngeal cancer and oral cancer was reported to be 0.49 (95% CI = 0.20-1.43) and 4.20 (95% CI = 1.32-13.3), respectively. One study that evaluated risk in different head and neck cancers reported 2-fold OR (2.73 [95% CI = 1.65-4.41]). CONCLUSION: On the basis of our evaluation, there is an association of WPS with head and neck cancer. However, larger studies with standardized methods are needed to identify the possible detrimental health effects of WPS more fully.

Molecular and immunohistochemical analyses of uveal melanoma patient cohort.

Uveal melanoma is a rare form of melanoma and the most frequent primary eye malignancy in adults. The major molecular alterations underlying uveal melanoma pathogenesis affect mainly the GNAQ, GNA11, SF3B1, and BAP1 genes. In this study, we somatically genotyped 31 Brazilian uveal melanomas for BRAF, GNA11, GNAQ, SF3B1, and BAP1 gene mutations and assessed BRCA2 and p53 protein expression. GNAQ and GNA11 mutations were detected in 60%, and SF3B1 mutation rate was 30%. p53 Immunostaining was markedly positive in 5/31, and 3/31 samples showed negative BRCA2 expression. This study supports the importance of these key genes in uveal melanoma tumorigenesis; p53 and BRCA pathways seem to play a role in a subset of patients, possibly heralding unfavorable prognosis.

Familial STAG2 germline mutation defines a new human cohesinopathy.

We characterize a novel human cohesinopathy originated from a familial germline mutation of the gene encoding the cohesin subunit STAG2, which we propose to call STAG2-related X-linked Intellectual Deficiency. Five individuals carry a STAG2 p.Ser327Asn (c.980 G > A) variant that perfectly cosegregates with a phenotype of syndromic mental retardation in a characteristic X-linked recessive pattern. Although patient-derived cells did not show overt sister-chromatid cohesion defects, they exhibited altered cell cycle profiles and gene expression patterns that were consistent with cohesin deficiency. The protein level of STAG2 in patient cells was normal. Interestingly, STAG2 S327 is located at a conserved site crucial for binding to SCC1 and cohesin regulators. When expressed in human cells, the STAG2 p.Ser327Asn mutant is defective in binding to SCC1 and other cohesin subunits and regulators. Thus, decreased amount of intact cohesin likely underlies the phenotypes of STAG2-SXLID. Intriguingly, recombinant STAG2 p.Ser327Asn binds normally to SCC1, WAPL, and SGO1 in vitro, suggesting the existence of unknown in vivo mechanisms that regulate the interaction between STAG2 and SCC1.

Ameloblastic carcinoma: a Brazilian collaborative study of 17 cases.

AIMS: Ameloblastic carcinoma (AMECA) is an odontogenic malignancy that combines the histological features of ameloblastoma and cytological atypia. Because of its rarity, it poses difficulties in diagnosis. The aim of this study was to investigate the socio-demographic data, histopathology, immunohistochemical features, treatment and outcomes of 17 cases. METHODS AND RESULTS: Descriptive statistical analyses were used to portray the clinicopathological data collected, retrospectively. Log-rank tests were performed to determine new prognostic factors. Lesions were immunostained for Ki67, p16, p53, and cytokeratins (CKs), and compared with solid/multicystic ameloblastomas (n = 15). AMECA was mostly diagnosed at a late stage, affecting the posterior mandible of male patients in their fifth decade of life. Recurrence was diagnosed in nearly 90% of treated patients, and metastasis occurred in four patients. The mean number of Ki67-positive cells was 86.4 ± 66 per field. Tumours were focally positive for CK7, CK8, CK14, and CK18, and diffusely positive for CK19, p53, and p16. AMECA showed increased immunoexpression of CK18, CK19, p16, p53 and Ki67 as compared with benign cases. CONCLUSIONS: Our study has contributed to the improved characterization of the epidemiology, prognostic markers, treatment options and outcomes of AMECA. Current criteria must be reviewed to simplify the diagnostic process for these neoplasms.

Association between histopathological features of dysplasia in oral leukoplakia and loss of heterozygosity.

AIMS: Oral leukoplakia (OL) dysplasia is graded on the basis of architectural and cytological features, and grade does not correlate well with malignant transformation. Loss of heterozygosity (LOH) profiles have been validated as risk predictors of OL malignant transformation. We aimed to assess whether the histological parameters used to grade dysplasia show different LOH profiles. METHODS AND RESULTS: Areas of epithelial dysplasia of 29 OL samples were microdissected, and LOH was assessed by use of a panel of 11 microsatellite markers located on chromosomes 3, 9, 11, and 17. Dysplasia was graded, and the cytological and architectural parameters were scored. Dysplasia was graded as mild in 18 samples, moderate in nine, and severe in two. The moderate/severe dysplasias and the mild dysplasias did not show different frequencies of allelic loss. Irregular epithelial stratification was associated with LOH at marker D3S1234 (3p14.2). In addition, the presence of drop-shaped rete ridges and premature keratinization in single cells showed associations with LOH at D9S162 (9p22) and P53 (17p13.1), respectively. CONCLUSIONS: We provide evidence that architectural and cellular changes in OL have different LOH patterns.

BRAFV600E Mutation in Melanotic Neuroectodermal Tumor of Infancy: Toward Personalized Medicine?

The melanotic neuroectodermal tumor of infancy (MNTI) is a rare neoplasm that primarily affects the maxilla of infants during their first year of life. Complete resection is the conventional treatment and recurrence rates vary from 10% to 60%. The recurrent tumors grow more aggressively and can invade other anatomic structures, such as the nasal cavity, the orbit, and the skull base. The aggressive behavior of MNTIs may require radical resection, which may not be possible in some cases because of its rapid and invading growth together with invasion of vital structures. In these situations, adjunct radiotherapy or chemotherapy has been used. However, as there are no conclusive data regarding the molecular profile of this tumor, currently there is no targeted therapy that may be used in the treatment of selected aggressive cases. On the basis of MNTI similarities with melanomas, such as derivation from the neural crest cells and presence of large melanin-containing cells, we hypothesized that MNTIs also may harbor the BRAFV600E oncogenic mutation. We show for the first time that this important pediatric tumor may harbor the oncogenic BRAFV600E mutation, providing the first insights to their personalized treatment.

Defects of the Carney complex gene (PRKAR1A) in odontogenic tumors.

The surgical treatment of some odontogenic tumors often leads to tooth and maxillary bone loss as well as to facial deformity. Therefore, the identification of genes involved in the pathogenesis of odontogenic tumors may result in alternative molecular therapies. The PRKAR1A gene displays a loss of protein expression as well as somatic mutations in odontogenic myxomas, an odontogenic ectomesenchymal neoplasm. We used a combination of quantitative RT-PCR (qRT-PCR), immunohistochemistry, loss of heterozygosity (LOH) analysis, and direct sequencing of all PRKAR1A exons to assess if this gene is altered in mixed odontogenic tumors. Thirteen tumors were included in the study: six ameloblastic fibromas, four ameloblastic fibro-odontomas, one ameloblastic fibrodentinoma, and two ameloblastic fibrosarcomas. The epithelial components of the tumors were separated from the mesenchymal by laser microdissection in most of the cases. We also searched for odontogenic pathology in Prkar1a(+) (/) (-) mice. PRKAR1A mRNA/protein expression was decreased in the benign mixed odontogenic tumors in association with LOH at markers around the PRKAR1A gene. We also detected a missense and two synonymous mutations along with two 5'-UTR and four intronic mutations in mixed odontogenic tumors. Prkar1a(+) (/) (-) mice did not show evidence of odontogenic tumor formation, which indicates that additional genes may be involved in the pathogenesis of such tumors, at least in rodents. We conclude that the PRKAR1A gene and its locus are altered in mixed odontogenic tumors. PRKAR1A expression is decreased in a subset of tumors but not in all, and Prkar1a(+) (/) (-) mice do not show abnormalities, which indicates that additional genes play a role in this tumor's pathogenesis.

Hsp27 (HSPB1) differential expression in normal salivary glands and pleomorphic adenomas and association with an increased Bcl2/Bax ratio.

Pleomorphic adenoma (PA) is the most common salivary gland neoplasm. The Hsp27 (HSPB1) is an antiapoptotic protein whose synthesis follows cytotoxic stresses and result in a transient increase in tolerance to subsequent cell injury. Although Hsp27 is expressed in a range of normal tissues and neoplasms, a wide variation in its expression exists among different cells and tissues types. In certain tumours of glandular origin (such as oesophageal adenocarcinomas), the level of Hsp27 is decreased. In the present study, Hsp27 protein levels were evaluated by enzyme-linked immunosorbent assay (ELISA) in a set of 18 fresh PA and 12 normal salivary gland samples. In addition, we tested if Hsp27 protein levels correlated with p53 expression and cell proliferation index, as well as with the transcriptional levels of Bcl-2-associated X protein (BAX), B cell lymphoma 2 (BCL2) and Caspase 3 in PA. We further tested the association between Hsp27 expression and PA tumour size. While all normal salivary gland samples expressed Hsp27 protein, only half of the PA samples expressed it, resulting in a reduced expression of Hsp27 in PA when compared with normal salivary glands (P = 0.003). The expression levels of this protein correlated positively with a higher messenger ribonucleic acid (mRNA) ratio of Bcl2/Bax (R = 0.631; P = 0.01). In conclusion, a decreased Hsp27 protein expression level in PA was found. In addition, Hsp27 levels correlated positively with the Bcl2/Bax mRNA ratio, suggesting an antiapoptotic effect.

Cell phone use and parotid salivary gland alterations: no molecular evidence.

BACKGROUND: The association between cell phone use and the development of parotid tumors is controversial. Because there is unequivocal evidence that the microenvironment is important for tumor formation, we investigated in the parotid glands whether cell phone use alters the expression of gene products related to cellular stress. METHODS: We used the saliva produced by the parotid glands of 62 individuals to assess molecular alterations compatible with cellular stress, comparing the saliva from the gland exposed to cell phone radiation (ipsilateral) to the saliva from the opposite, unexposed parotid gland (contralateral) of each individual. We compared salivary flow, total protein concentration, p53, p21, reactive oxygen species (ROS), and salivary levels of glutathione (GSH), heat shock proteins 27 and 70, and IgA between the ipsilateral and contralateral parotids. RESULTS: No difference was found for any of these parameters, even when grouping individuals by period of cell phone use in years or by monthly average calls in minutes. CONCLUSION AND IMPACT: We provide molecular evidence that the exposure of parotid glands to cell phone use does not alter parotid salivary flow, protein concentration, or levels of proteins of genes that are directly or indirectly affected by heat-induced cellular stress.

Progress towards personalized medicine for ameloblastoma.

Ameloblastoma is a locally infiltrative benign odontogenic neoplasm. Tumours may be large, destructive and recurrent, requiring radical surgery with associated facial deformity and morbidity. The molecular pathogenesis of this tumour has been unclear, retarding the development of non-invasive gene-targeted therapies. In a recent paper in this journal, Kurppa et al. [4] showed that EGFR-targeted therapy blocked cell proliferation in an ameloblastoma primary cell culture. That this therapy was not effective in another primary cell culture led to the discovery of the oncogenic BRAF V600E mutation in a high proportion (63%) of ameloblastoma samples. By defining two separate pathways, both of which can be specifically targeted, these findings are an important step towards personalized medicine of ameloblastoma. We discuss the findings in the broader context of ameloblastoma, as well as the effects of tumour microenvironment and molecular heterogeneity that need to be taken into account when considering the use of personalized therapies based on specific genetic mutations in individual patients.

TP53 single nucleotide polymorphism rs1042522 in salivary gland neoplasms.

BACKGROUND: The TP53 single nucleotide polymorphism (SNP) rs1042522 encodes arginine (Arg) or proline (Pro). The Arg variant is more effective at inducing apoptosis than the Pro. METHODS: We assessed this SNP through direct sequencing of benign and malignant salivary neoplasms of Brazilian patients and compared the results with healthy controls' data. BAX, BCL-2, and CASPASE-3 mRNA levels were assessed by quantitative polymerase chain reaction (qPCR) in a set of salivary tumors, and the results were correlated with the tumor genotype. RESULTS: We found a higher frequency of the Arg/Arg genotype in the malignant group. However, the SNP did not influence the age of onset in either benign or malignant tumors. The SNP was not associated with the transcription levels of apoptotic/antiapoptotic genes. CONCLUSION: Malignant salivary neoplasms showed a higher frequency of the allele encoding Arg and a higher frequency of the Arg/Arg genotype. However, the different genotypes did not impact the transcription of genes involved in apoptosis.